Panels of this type are used to provide separate work areas with some or all of the work facilities such as work surfaces, storage facilities and work organizing accessories mounted on the panels. The brackets are detachably secured to the panels by hooking them to rigid, slotted standards or strips provided along each vertical edge of the panel. The brackets mount a beam which extends across the face of the panel and the accessories, in turn, are mounted on the beam. Such an arrangement is described in co-pending application, Ser. No. 269,417, entitled "Accessories For Movable Partition Systems", filed June 1, 1981, and having a common assignee. This invention provides a means of securing accessories utilizing the same beam construction to panels which do not have the rigid attachment standards along each edge normally used to secure the accessory supporting brackets. The absence of the rigid edge supports creates a problem because the accessories should be capable of being mounted at various heights and of relocation from panel to panel without leaving a damage mark on the panel's surface. Also the accessories must be rigidly supported and the supports must be capable of withstanding substantial cantilevered loads.